The UN Security Council has expressed "serious concern" at mounting reports of illegal arms transfers from Syria to Lebanon and authorised an independent mission to be deployed quickly to assess how the frontier is being monitored.
A presidential statement adopted by the council welcomed the Lebanese government's determination and efforts to prevent arms transfers, which are banned under UN resolution 1701 that ended last summer's war between Hizbullah and Israel.
The council noted that the Syrian government said it has taken measures to prevent arms transfers. It reiterated its call on Syria "to take further measures to reinforce controls at the border."
Alluding to the current political stand-off between pro and anti-Syrian forces in Lebanon, the council called on Lebanese political parties "to show responsibility with a view to preventing, through dialogue, further deterioration of the situation in Lebanon."
The council adopted the statement as Secretary-General Ban Ki-moon headed to Europe and the Middle East on a week-long trip that will end in Syria.
Mr Ban told reporters he planned to discuss "all matters" concerning the implementation of relevant Security Council resolutions with Syrian President Bashar Assad and other officials in Damascus, "particularly the situation in Lebanon."
The presidential statement urged all countries, "especially in the region," to enforce a UN arms embargo. The original draft had singled out Syria and Iran.
The council reiterated its call "for disbanding and disarmament of all militias and armed groups in Lebanon."
When the council receives recommendations from the secretary-general, it said members will "take further concrete steps to achieve the goals" of banning the sale or transfer of arms or technical assistance to any entity or individual not authorised by the Lebanese government.
In late March, Mr Ban warned during a visit to Lebanon that arms smuggling from Syria could threaten the ceasefire in Lebanon and urged full compliance with UN resolution 1701 that ended the 34-day Israeli-Hizbullah war.